Page:Foods and their adulteration; origin, manufacture, and composition of food products; description of common adulterations, food standards, and national food laws and regulations (IA foodstheiradulte02wile).pdf/289

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When properly leavened and kneaded and baked these quantities of materials will make a loaf of bread weighing 2750 grams.

Average Composition of Bread.—In the following tables are given the average composition of bread of different classes. Class 1 is composed of loaves of the so-called Vienna or French type; Class 2 consists of what is known as home made bread or bread baked at the home and not in the bakery; Class 3 consists of bread made from graham flour; Class 4 consists of bread made largely of rye flour; Class 5 is a second collection of home made bread which may be very properly compared with Class 2; Class 6 consists of bread of miscellaneous origin bought on the open market. The data given represent the mean composition of numbers of samples (Bull. 13, Bureau of Chemistry):

                          Moisture. Protein. Ether Fiber. Ash. Starch and Salt. Calories.
                                               Extract. Sugar.

Class 1. Perct. Perct. Perct. Perct. Perct. Perct. Perct.
                          38.71 8.09 1.06 .62 1.19 53.72 .57 —
In the dry substance, — 13.23 1.73 .97 1.95 83.10 .93 4458

Class 2.
                          33.02 7.24 1.95 .24 1.05 56.75 .56 —
In the dry substance, — 10.80 2.91 .36 1.55 84.75 .84 4497

Class 3.
                          34.80 8.15 2.03 1.13 1.59 53.40 .69 —
In the dry substance, — 12.51 3.13 1.74 2.29 82.06 1.07 4434

Class 4.
                          33.42 7.88 .66 .62 1.84 56.21 1.00 —
In the dry substance, — 11.86 1.02 .95 2.79 84.36 1.50 4395

Class 5.
                          36.16 7.10 1.14 .26 1.06 54.53 .58 —
In the dry substance, — 11.17 1.75 .41 1.68 85.41 .92 4395

Class 6.
                          34.41 6.93 1.48 .30 1.00 56.18 .49 —
In the dry substance, — 10.59 2.21 .46 1.53 85.66 .76 4401

A Typical American High-grade Yeast Bread.—In conjunction with the actual analyses given above it is of interest to combine as many analytical data as can be conveniently secured for the purpose of determining what the average composition of a high-grade typical yeast bread is. This comparison leads to the following composition:

Moisture, 35.00 percent
Protein, 8.00 "
Ether extract, .75 "
Starch and sugar, 54.45 "
Fiber, .30 "
Ash, 1.50 "

Of the ash mentioned in the above analysis .50 percent may be ascribed to the natural mineral ingredient of flour and 1 percent to added salt.

The chief variations from the typical composition of bread made from high-grade flour are found in the moisture and ether extract. The moisture may rise above 40 percent in breads made of flour rich in gluten or sink to 30 percent or under when flour of an inferior gluten content is employed. The quantity of ether extract depends chiefly upon the amount of milk which is used in the making of bread and the amount of fat employed either in the